function dx = func1(t, x, wa, T) 
    % 单物种无环境
    global w v 
    dx = zeros(3, 1); 
    H1 = 0.8; H2 = 0.4; H3 = 0.2; 
    N1 = 2000; N2 = 2000; N3 = 2000; 
    %sigma21 = 0.7; sigma32 = 0.7; sigma31 = 0.49; 
    %sigma12 = 0.8; sigma23 = 0.8; sigma13 = 0.64;    

    %sigma21 = 0.999; sigma31 = 1.01;
    %sigma32 = sigma31/sigma21; sigma13 = 1.5/sigma31;
    %sigma12 = 1.5/sigma21; sigma23 = sigma21/sigma31;   
%     k1 = 2; k2 =2.2;  
%     u = water(wa); y = temp(T); 
%     sigma = k1*u*(1-w)+k2*y*(1-v); 
    dx(1) = H1*x(1)*(1 - x(1)/N1); 
    dx(2) = H2*x(2)*(1 - x(2)/N2); 
    dx(3) = H3*x(3)*(1 - x(3)/N3); 
end